Valve and switch unit



1947. A. K FOULDS 2,428,7 51

' VALVE AND SII'I'CH UNIT Filed Nov. 29, 1944 FIG. I 51 l i 6/ 9 I00 m INVENTOR.

Patented Oct. 7, 1947 VALVE AND SWITCH om'r Andrew K. Foulds, Grosse Pointe, Micln, assignor to Detroit Lubricator Company, Detroit, Mich., a corporation of Michigan Application November 29, 1944, Serial No. 565,773

The invention relates to a fuel burning system such as an oil burner and it has particular relation to a valve and switch unit for controlling the flow of fuel and operation of a fan or blower forming part of the system.

In one type of oil burner, oil is supplied to the burner through a valve which is adjustably controlled in a manner depending upon the type of fire required. For instance, if the space to be heated requires heat, more oil is supplied to the burner and when the temperature of the space increases sufilciently the amount of oil supplied is reduced so-that only a small fire is maintained. Generally, in this type of burner a fan or blower .is controlled in such manner that more air flows to the burner when the larger amount of oil is being supplied and when the amount of oil is reduced the fiow of air is reduced. Equipment of this type is controlled by a valve and an electrical switch governing operation of the fan.

One object of the present invention is to provide improvements in the equipment for the purpose indicated wherein the electrical switch controlling the fan operation forms an'operating part of the valve controlling device.

Another object of the invention is to provide the improved arrangement such as designated wherein the electrical switch is embodied in a casing which acts as an operating part of the valve device so that forces controllin the valve operation are imparted through the switch casing.

Another object of the invention is to provide an arrangement of the character indicated wherein opening of the electrical switch controlling the fan operation is delayed if the valve is operated to reduce the full fuel so as to permit a temporary continued operation of the fan until oil already supplied to the burner is reduced in quantity.

Another object of the invention is to provide a valve operating and switch control unit which may be easily attached to existing forms of fioat valve casings so as thereby to permit use of the invention in connection with existing equipment.

Another object of the invention is to provide equipment such as indicated which may be manufactured and assembled inexpensively.

Other objects of the invention will become apparent from the following description, from the drawing to which it relates and from the claims hereinafter set forth.

For a better understanding of the invention ing wherein:

, Figure 1 is a vertical section of a control device Claims. (Cl. 200-53) 2 constructed according to one form of the invention; and r Fig. 2 is a similar view showing another form of the invention.

Referring to Fig. l, a float valve casing is indicated at l0 and this comprises a body having a bottom II, side wall i2 and a cover l3. The bottom II has an upwardly extending projection I! which is apertured as indicated at I6 to permit fuel to flow downwardly therethroughaifd below this projection, a conduit i8 is connected to the bottom. This conduit leads to an oil burning device which in this case may be a pot type of burner having a. pilot fire. Above the opening it, a valve seat I! is provided at the upper end of the projection l5 and this seat is adapted to cooperate with a frusto-conical surface 2! on a valve stem reference may be had to the accompanying draw- 22. Below the frusto-conical surface 2 i the valve stem has a. smaller portion 23 movable through the opening it and this smaller portion has tapered grooves 2|.

The valve is shown in its closed position but it will be seen that as it is raised from the seat l9, the amount of oil that will flow through the valve will depend upon the extent the tapered groove 24 projects above the upper end of the opening l6. Depending upon the position of the valve stem 22, therefore, the amount of oil which will fiow downwardly and to the burner may be relatively large so as to support a high fire or small so as to support a low fire or the flow of oil may be entirely out off.

A spring 2| is provided on the valve stem and this spring at its upper end engages the cover I! while at its lower end it engages a collar 21 on the valve stem. Thus, the stem normall urges the valve towards a closed position. The stem projects through an opening in the cover 13, and at its upper end it is connected to a sheet metal frame 29 which has inwardly turned legs or flanges 30 and 3| at its lower end which overlap and lay over the upper end of the stem. A screw 32 extending downwardly through an opening 33 in the flanges, and which is threaded into an opening 34 in the upper end of the stem, connects the latter to the frame. The casing or frame 29 includes side walls It and 31 and a top wall 38 and it is evident that the frame may be readily constructed from sheet metal.

Towards its lower end, the side wall 31 has a struck out finger 40 and this finger has an opening ll through which a screw 42 passes. The lower end of the screw is threaded into the cover l3 so as to be adjustable and the screw may be locked in any position of adjustment by a lock nut 43 adapted to be turned tightly against the upper side of the cover. At its upper end, the screw has a head 44 and it is now evident that upward movement of the valve stem 22 may be adjustably limited by adjustment of the screw 42 so as thereby to limit the amount the valve can be opened. Thus, this screw controls the high fire position of the valve stem. l

A similar screw 46 threaded through the cover I! is disposed below the flange II of the frame so as to limit downward movement thereof and hence downward movement of the valve stem. Therefore, whether or not the valve is fully closed or is almost closed so as to supply a small amount of fuel for low fire depends upon the position of the screw 46. A lock nut ll holds the screw II in position.

Opposite side edges of the vertical wall I! have inwardly turned legs in and ll respectively so as to provide a vertical channel or guideway and similar legs 52 and I! on the wall 31 provide a guideway at the opposite side of the frame. These channels or guideways slidably receive a switch casing 55 which may be formed from suitable insulating material as will be readily understood. The switch may be of a standard snap action type having a pin or element 58 projecting above its upper surface for engagement with a screw 51 in the wall 38 and when this pin is moved downwardly, the switch is closed in a snap action manner and when the pin is allowed to move upwardly by spring action of the switch construction, the switch opens in a snap action manner. A switch known in the trade as the "ACRO snap switch is satisfactory for this purpose.

At its lower side, the switch casing is provided with terminals 50 and 59 and these are connected to wires i0 and 8! in the circuit of a motor 62 .which operates a blower or fan adapted to supply air to the burner. When the pin 58 is moved downwardly relative to the switch casing the switch closes and the motor 82 operates the blower or fan and then when the switch element moves upwardly relative to the switch casing the motor I! is stopped.

Below the switch casing, an insulating frame element 65 is also mounted for sliding movement in the channels and this frame element has opposite legs 68 and 61 abutting the bottom of the switch casing. The element I! has a downwardly open recess or well 68 and within this well a spring 10 is provided which, at its upper end, abuts the bottom wall of the recess and at its lower end a disc element 1| slidably but closely fitting in the well. A flexible rubber diaphragm i2 is connected to the center of the disc by means of a rivet 13 having a substantially large head 14 for supporting the central and underside of the diaphragm and the diaphragm is slightly smaller than the disc II and is movable upwardly into the well 89.

One or more openings 15 are provided in the disc so as to be covered by the diaphragm l2 and these openings serve as valve apertures. Now, if the head 14 on the rivet element is moved upwardly, the disc and diaphragm move upwardly against the action of the spring 10 and any air within the well can escape through the openings 15 as the edge portions of the diaphragm 12 will flex downwardly so as to allow the air to flow outwardly between the diaphragm and disc. The disc and diaphragm are allowed to move downwardly by slight air leakage either past the edges of the disc and diaphragm or, if desired. a small opening may be provided in the wall of the element l5. It should be understood from this that the structure. thus described provides a dashpot which allow rapid movement of the disc upwardly into the well but only a relatively slow return movement.

A bi-metallic element I1 is mounted on a bracket 18 secured to the cover I! by a screw 10 and this bi-metallic element extends inwardly through an opening in the frame 2! and under the rivet head 14. A heating element I is attached to the bi-metallic element and the arrangement is such that when electric current flows through the heating element. II the bimetallic element moves so as to press upwardly against the rivet head 14 and when the heating element cools, reverse movement of the parts occurs. The heating element II is connected to wires 82 and N forming part of a circuit including a transformer l4 and a thermostat II. This thermostat may be located in the room to be heated.

With the parts as shown, the thermostat is open. No oil is flowing to the burner, and the blower motor I! is not operating. When heat is required in the room, the thermostat I! closes and this causes the element .0 to becom heated and the bi-metallic element 11 to move upwardly against the rivet head 14. The first part of this movement causes the dashpot element 85 and switch casing 55 to move upwardly so as to press the switch operating element 50 against the screw 51 in the upper wall ll of the frame 29. Thus, the switch is closed thereby causing the motor '82 to operate.

As the bi-metallic element continues to move upwardly, the disc 1| moves upwardly into the well 89 thereby compressing the spring Ill and during this time, the switch casing 55 is held against upward movement by the pin it having reached the lower limit of movement within the switch casing. If desired, a separate stop might be provided between the upper wall 18 of the frame 28 and the switch casing 55 so that the switch casing 55 would abut the stop directly after the pin SI has been moved to close the switch. The same result might be accomplished by having stops on the upper ends of the guideways so that the switch casing could only move so far upwardly but suiilciently for causing the switch to close.

When resistance to movement of the disc upwardly in the well 8! becomes sufllcient such as when the spring reaches a closed condition, further movement of the bi-metallic element will cause the entire frame 2! to move upwardly thereby overcoming the spring 28 on the valve stem and elevating the stem to open the valve. This opening movement continues until the adjusting screw 42 stops the movement. The burner now operates at a high fire stage with a larger quantity of 011 being supplied. When the room is heated suiilciently to cause the thermostat to open, bi-metallic element 11 begins a return movement as it cools and the spring 28 first returns the valve to its lower position. When the valve stem reaches its lower position, the spring Ill pressing against the bottom surface of the well it holds the pin 58 in a switch closed position and as the bi-metallic element continues its return movement, the disc will gradually move while still holding the switch closed. Finally, the force of the expanding spring is less than the switch spring action and .the switch opens so as to stop the fan motor 82. From this, it will be seen that there is a delayed action in the opening of the switch as the valve is closed or moved to its lower position. This is desirable since the 'blower will continue to operate and supply air to the burner so as to support high fire combustion until the relatively large amount of oil in the burner is consumed to a low fire stage.

In the form of the invention shown by Fig. 2 the valve stem 12 is urged upwardly to an open position by a spring 88 and the open end of the stem above the cover l3 abuts the-switch casing 55 directly. This casing is held in a metal frame 89 which is slidable in a guide element 90 secured by screws 9i to the cover. The frame 89 above the casing 55 is shaped to provide a tubular guide 92 and in this guide a pin 93 is slidably mounted for movement in a vertical direction. The lower end of the pin 93 contacts the switch pin 56 while the upper end of the pin contacts the bi-metallic element ll. For normally urging the pin 93 upwardly a spring 94 is provided which abuts at its lower end the casing 55 and at itsupper end a collar '95 on the pin. In this assembly, the bimetallic element 11 is fastened to the element 90 instead of to the cover l3 so as to place the bimetallic element above the switch.

For limiting movement of the switch casing 55 and valve stem 22 upwardly, a turnable pin 99 extends through the side wall of element 90 and is provided with an eccentrically mounted head 91 disposed in the path of the switch casing and frame 89. A spring 98 around the pin 95 and abutting the element 99 and a knurled head 99 on the outer end of the pin frictionally holds the pin in position. It is evident that when the pin is turned, the head 91 may be changed so as to vary the distance the switch casing may move upwardly. A similar pin I00 below the switch casing 55 limits the amount the valve stem can move downwardly so that the valve can be held slightly open for low fire.

When the thermostat 95 closes so as to require heating of the heating element 90, this causes the bi-metallic element 11 to function and as a result the element moves upwardly. The spring 94 is stronger than the spring 98 and the first movement of the bi-metalllc element causes the pin 93 to move upwardly relative to the switch casing thereby allowing the switch pin 56 to move so as to close the switch. It should be stated here that in this form of the invention the electrical connections on the switch are such that upward movement of the pin closes the switch across the terminals, whereas in Fig. 1, the downward movement of the pin closes the switch across the terminals. Two switches are really present, one closed when the pin is moved downwardly and the other when it is moved upwardly and in Fig. 1 one of the switches is used and in Fig. 2 the other is used.

Continued movement of the bi-metallic element and expansion of spring 94 finally may press the collar 95 against the frame 89 and then spring 99 opens the valve so as to supply oil for the high fire stage. When the thermostat opens, a reverse movement occurs and the valve first closes or' moves to' its low fire position. Then the spring 94 is compressed and finally the switch is opened.

It is evident, that in either form of the invention a unit is provided including a switch, which may be quickly and easily attached to the valve casing and to the valve stem, and that the switch itself forms an intermediate part of the means for moving the valve and hence it is operatively between the bl-metallic element and the valve 6 stem. It is also evident that in either case, the motor operating the fan continues operating for a period after the valve is moved .to its closed or low fire position and hence that air will be supplied for consuming oil present in the burner.

Furthermore, in the construction shown by Fig. 1, a further delay occurs before the blower ceases operating so as to allow more time for consuming the oil in the burner. The simplicity of the invention is such that it may be manufactured inexpensively and then assembled with existing forms of valve controls, merely by attaching it to the covers of valve casings now in use.

Although more than one form of the inventionhas been illustrated and described in detail, it will be apparent to those skilled in the art that various modifications may be made without departing from the scope of the appended claims.

What is claimed is:

1. In a combined valve and switch device, a

'valve member, a bodily movable switch casing said operating means to said valve member.

2. In a combined valve and switch device, a valve member, a bodily movable switch casing having a switch operating pin projecting therefrom, operating means for said valve member and said switch pin, means including said switch casing for transmitting movement from said operating means to said valve member, and means cooperable with said operating means to actuate said pin prior to opening movement of said valve member.

3. In a combined valve and switch control device, a bodily movable switch casing having a switch operating pin projecting from the casing, a. valve member operatively connected to said casing for movement thereby, means acting through said casing to move said valve member, and means to actuate said pin.

4. In a combined valve and switch device, a valve member, a bodily movable switch casing, means operable to transmit movement from said switch casin to said valve member, a switch operating pin projecting from said switch casing, operating means for moving said casing and said pin, and resilient means operable to transmit movement from said last-named operating means to said switch casing.

5. In a combined valve and switch device, a valve member, a bodily movable switch casing having a switch operating pin projecting therefrom, operating means for said valve member and said switch pin, and means including said switch casing and said pin for transmitting movement from said operatin means to said valve member.

6. In acombined valve and switch device, a valve member, a bodily movable switch casing having a switch operating pin projecting therefrom, a frame carried by said valve member and slidably supporting said switch casing, an abutment on said frame engageable by and for actuating said switch pin, said pin transmitting movementirom said casing to saidframe, and an operating member for moving said switch casing to actuate said pin and to move said frame.

7. In a combined valve and switch device, a valve member, a bodily movable switch casing having a switch operating pin projecting therefrom, a frame carried by said valve member and slidably supporting said switch casing, an abutment on said frame engaseable by and for ac- 7 tuating said switch pin, said pin transmitting movement from said casing to said frame, an operating member for moving said switch casing to actuate said pin and to move said frame, and

a dash-pot interposed between said operating member and said switch casing.

8. In a combined valve and switch device, a valve member, a spring urging said valve member toward one position, a frame secured on said valve member, means engageable with said frame to limit valve member movement, a snap switch casing slidably supported in said frame and having a switch operating pin projecting from said casing, said pin being ensageabie with said frame to operate said pin, operating means t move said casing in said frame to actuate said pin and being operable to move said valve member against the force of said spring, and means including said casing, said pin and said frame to transmit the movement of said operating means to said valve member.

9. In a device of the character described, a valve member having a stem, an operating means to move said valve member, a bodily movable switch casing having a switch operating pin projecting therefrom, a spring bearing against said casing, said spring and said casing being interposed between said operating means and said stem and being operable to transmit movement from said operating means to said stem, said spring being compressible upon limitation of movement of said valve member, means to limit closing movement of said valve member, and

8 means operable upon compression of said sprint to actuate said switch operating pin.

10. In a combined valve and switch device, a valve member, a switch casing supported on slid valve member and having a switch operatins Din projecting from said casing, a thrust member engageable with and for operating said pin, a spring interposed between said thrust member and switch casing to oppose operation of said pin by said thrust member and to transmit valve member operating movement from said thrust member to said switch casing, means to move said thrust member to actuate said valve and said switch pin, and means to limit movement of said switch casing so that said thrust member can actuate said pin.

ANDREW K. FOULDB.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS 

